In a mobile device such as a mobile telephone, a PDA, or a mobile game device, an acrylic resin plate which is excellent in transparency and lightweight has generally been used on a display screen thereof. In recent years, however, instead of the conventional acrylic resin plate, use has often been made of a cover glass formed of a glass material which has high strength even if it is thin and which is superior in various points such as surface smoothness, protectiveness (weather resistance, antifouling property), appearance, and high-quality image to the conventional acrylic resin plate.
Normally, on this cover glass, a character or figure pattern, such as a logo of a company or product name or marks of operation buttons, is formed by a printing method.
A relevant technique is disclosed in, for example, JP-A-2006-27023 (Patent Document 1).